Détails:The Sunderland flying boat arrived near Iwakuni NAS but the crew were told the sea was choppy due to a gusty wind. They decided to circle the area to wait for the weather to improve. It was dark by the time they attempted to land again. The airplane struck the sea heavily and overshot. The crew then decided to land after sunrise. After landing it struck heavy seas. The nose broke and the Sunderland came to rest on its back.